Turkish President Recep Tayyip Erdogan intensified his dispute with European nations yesterday, claiming that “Nazism is alive in the West” after two of his ministers were prevented from campaigning in the Netherlands and promising that the Dutch would “pay the price” for their unusual action.

While Dutch Prime Minister Mark Rutte worked to contain the diplomatic damage, Erdogan made it clear that Turkey would not be easily appeased.

He said Ankara would retaliate for the treatment of the Turkish family affairs minister, who on Saturday was blocked by police in riot gear from entering her country’s consulate in Rotterdam.

That came hours after Turkish Foreign Minister Mevlut Cavusoglu was denied airport landing rights to address crowds at a Rotterdam rally.

Saying that he was wrong to think Nazism was over, Erdogan made the comment to an audience in Istanbul. The remarks were similar to ones he made about Germany earlier this month.

The Dutch prime minster said it was important for his government not to bow to pressure from Turkey, especially after Ankara threatened sanctions if the Dutch kept Turkish ministers out.

“Turkey is a proud nation. The Netherlands is a proud nation. We can never do business under those sorts of threats and blackmail,” said Mark Rutte, whose party is locked in a neck-and-neck race with populist firebrand Geert Wilders.

To bolster support for an April 16 referendum that would expand the powers of Turkey’s president, Turkish cabinet ministers have scheduled campaign trips to several European countries with sizable populations of Turkish expatriates.

However, some European nations have complained that Turkey under Erdogan is slipping toward authoritarian practices, especially since last summer’s aborted coup. Rutte cited that concern in asking Cavusoglu not to come to the Netherlands.

The furor between two NATO allies comes at a crucial time in the Netherlands, where issues of Dutch identity, relations with migrant communities and Islam have taken center stage in the run-up to a national election on Wednesday.

Rutte’s actions, which came two days after several German municipalities canceled rallies that Turkish Cabinet ministers had planned to address, prompted Erdogan on Saturday to accuse the Dutch of being “Nazi remnants.”

Yesterday, he heaped on more criticism while demanding an apology from the Dutch.

“If you sacrifice Turkish-Dutch relations to the elections on Wednesday, then you will pay the price,” Erdogan warned.

“Those who unleash the dogs and their hatred will pay the price,” he added in reference to images showing police dogs biting pro-Erdogan protesters who gathered outside the consulate.

Dutch Foreign Minister Bert Koenders said no apologies would be forthcoming.

Addressing crowds at a campaign rally later, Erdogan called on international organisations to impose sanctions on the Netherlands and urged the European Union to speak out against the Dutch.

“What took place in the Netherlands was the trampling of diplomacy, international law, practice, decency. Is there a peep coming out of Europe? No. Why? Because they won’t bite one another. They are all the same. The Netherlands did not behave like a European Union member state governed by the rule of law, but like a banana republic.”

Amid the sparring, Cavosoglu was allowed to campaign yesterday in the northern French city of Metz a day after he was banned from speaking in the Netherlands. He told hundreds of supporters there that the Dutch would be forced to “account” regardless of an apology and called the Netherlands the “capital of fascism.”

Alain Carton, secretary general of the Metz prefecture, said the rally presented no threat to public order and was permitted in the name of the freedom of assembly.

France’s foreign minister, Jean-Marc Ayrault, called for the calming of tensions between some European countries and Turkey. He also urged Turkish authorities to “avoid excesses and provocations.”

About 100 supporters draped in Turkish flags greeted Cavusoglu as he reached the Centre des Congres of Metz.

“I am disappointed by Holland because they speak of democracy and freedom but it is not the case. To not allow a speech, it’s sad. We are all disappointed,” said Beatrice Bozkus, a Metz resident who attended the rally.

This combo image shows a Turkish flag, top, flying over the Dutch consulate in Istanbul shortly after a man climbed onto the roof and replaced the Netherlands’ flag, while on the bottom the Netherlands one is restored after the man was apprehended.

The Netherlands said Turkish attempts to campaign here touched at the heart of Dutch citizenship, although hundreds of thousands of residents have Turkish roots and many still feel committed to their ancestral homeland.

“The biggest problem in this case is that Turkey is talking about Turkish citizens who they want to talk to,” Rutte said. “These are Dutch citizens who possibly also have voting rights in Turkey.”

Still, added the prime minister, his government “will keep working to de-escalate where we can. If the Turks choose to escalate, we will have to react, but we will do everything we can to de-escalate.”

On Saturday, Turkey’s family and social policies minister, Fatma Betul Sayan Kaya, was denied entry to the Turkish consulate in Rotterdam, where she was to campaign for the upcoming referendum in Turkey.

After a tense standoff outside the consulate, she was escorted back to the German border.

Speaking to reporters Sunday at Istanbul’s main airport, Kaya condemned Dutch authorities’ “anti-democratic” actions which “trampled on freedom of expression and right to assembly.”

“We were subject to very rude and harsh treatment,” she said.

Earlier, a man climbed onto the roof of the Dutch consulate in Istanbul and replaced the Netherlands’ flag with the Turkish one.

Television footage showed a man standing on the roof of the building shouting Allahu akbar, Arabic for “God is great.” A small group of men holding Turkish flags were seen outside the consulate shouting “Damn Holland” and “Racist Holland.”

The private Dogan news agency reported that the consulate later took down Turkey’s flag and put the Dutch flag back up.

In Rotterdam, police arrested 12 people yesterday at a demonstration outside the consulate after police were hit by bottles and rocks.